Malicious PDF — malware analysis report

Static analysis result for SHA-256 928dd2f6fc279e70…

MALICIOUS

PDF

84.6 KB Created: 2021-09-18 12:52:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 215bc92d3d27e62f3b936bc3ef790357 SHA-1: f1737d729a17c9590398b352229df8ba2c05c401 SHA-256: 928dd2f6fc279e707f52b9e23d093c484718cf9b81fdd8906943934fe7cfae51
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains a link farm pointing to compromised WordPress sites and disposable domains, likely serving as a lure for users to download further malicious content. Although no scripts were explicitly extracted, the PDF structure and the presence of numerous external links suggest an attempt to redirect users to malicious sites, potentially exploiting PDF vulnerabilities or serving as a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://chcial.ru/uplcv?utm_term=samsung+galaxy+grand+prime+4g+marshmallow+update+download
    • http://afro-safari.com/upload/files/voruf.pdf
    • https://mk-sito.it/uploads/file/12970369064.pdf
    • https://yingzhaoliuart.com/upload/file/32181697137.pdf
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/b082964fa5030005449ca1931edb9419/jowuzerutopomupidegesukes.pdf
    • https://pakistanchristiancongress.org/userfiles/file/87142368733.pdf
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb6e7cb3f8---wofudaposefexa.pdf
    • http://gemcom.org/userfiles/file/lunefubugigodu.pdf
    • http://www.cbs-emballages.com/upload/file/28384374361.pdf
    • http://jingyitech.com/uploadfile/denogonuraribuzedegul.pdf
    • http://mientrungland.net/uploads/image/files/26574982290.pdf
    • http://koszyczarek.pl/userfiles/file/90402520614.pdf
    • https://journeywithmypet.com/ckfinder/userfiles/files/korigonegasifudu.pdf
    • http://jeanthompson.nl/ckfinder/userfiles/files/2856667044.pdf
    • https://hanomanberjaya.com/contents/files/donewikusumale.pdf
    • http://etalentlink.com/uploadfile/file///2021091802095484.pdf
    • http://www.me.ntou.edu.tw/ckfinder/userfiles/files/20210907_040458.pdf
    • https://digireg.ru/upload/36255792496.pdf
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161364f301d209---sifaratos.pdf
    • http://gamax-motor.cz/data/dokumenty/48745398645.pdf
    • https://akproauto.com/nbloom/fckuploads/file/fikujapediw.pdf
    • http://schokobrunnen.com/idata/71295102892.pdf
    • http://gayaarchi.com/userfiles/file/20210918111036.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e3d4.bin
1245b392635374d52daec2f7f29d06d0bc8d6ff66de09e339fdf382f221397b0
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3D4 17624 bytes
font_01_sfnt_off000111d2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x111D2 16792 bytes
font_02_sfnt_off000129e9.bin
4b46a5b81126121598ab87d39c2a4657865640d22fca96c0adc1ef1cb7a53462
pdf-font-stream PDF embedded font (sfnt) at offset 0x129E9 11396 bytes